Needle cylinder for sinker-type circular knitting machines



B. FRIED July 19, 1960 NEEDLE CYLINDER FOR SINKER-TYPE CIRCULAR KNITTING MACHINES Filed Feb. 14, 1958 BENJAMIN FRIED INVENTOR.

AGENT NEEDLE CYLINDER FOR SINKER-TYPE CIR- CULAR KNITTING MACHINES Benjamin Fried, 2197 Cruger Ave., Bronx, NY.

Filed Feb. 14, 1958, Ser. No. 715,297 7 Claims. 01. 66-115) The present invention relates to circular knitting machines of the general type including a sinker top needle cylinder carrying axially reciprocating needles and radially reciprocating sinkers, and more particularly to im: provements in the sinker mounting.

In operating knitting machines of the above type, tubular knitted goods are manufactured by the cooperating reciprocating movement of the needles and the sinkers, the needles being mounted in the needle cylinder or on its periphery for up-and-down movement While the sinkers ride on the upper rim of the cylinder and move back-and-forth in a radial direction The needles and sinkers are arranged in interdigi'tating relationship so that their reciprocating movements knit the threads into a fabric, as is well known per se. This operation of knitting machines is entirely conventional. As experience has shown, it causes considerable collection of sludge or lint at or near the rim of the needle cylinder where the sinkers and' needles cooperate to knit the threads into a fabric.

The accumulation of sludge or lint is particularly bothersome in the conventional guide slots for the inner ends of the sinkers and in pockets formed between these guide slots and the needles moving on the periphery of the needle cylinder. This accumulation of dirt isespecially pronounced in fine-gage knitting machines using as many as 32-34 sinkers per inch. It appears to a smaller or larger degree in all machines and regardless of the thread material, being most strongly noticeable in the knitting of wool and some of the more recently developed synthetic fibers, such as Orlon, Acrilan and others. p

When dirt accumulates in the sinker guide slots, the collected dirt will tilt the sinkers out of their horizontal position on the cylinder rim, causing vertical unevenness in the knitted pattern and other operation troubles. When dirt clogs the pockets between the sinker guide slots and the needles, it eventually begins to bend the needles outhave been made to provide means for cleaning needle 2,945,368 Patented July 19, 1960 Other objects and advantages of the invention will become clear from the following detailed description of certain preferred embodiments thereof, taken in conjunction with the accompanying drawing wherein Fig. 1 is a perspective view of a sinker mounting according to one embodiment of the invention;

Fig. 2 is a section along line II-II of Fig. 1;

Fig. 3 is a vertical section of the upper portion of a knitting cylinder showing another embodiment of the sinker mounting; and

Fig. 4 is a sectional view similar to Fig. 2 but showing yet another embodiment of the sinker mounting.

Conventional portions of the needle cylinder, including all of the needle mounting and the sinker mounting except for the positioning of the sinker guide slots, may take any desired form and are accordingly either not shown at all or shown diagrammatically to facilitate the clear understanding of the structure of the invention proper.

In accordance with the present invention, there is'provided a needle cylinder for a circular knitting machine, wherein the radial sinker guide slots holding the inner ends of the sinkers are spaced from the cylinder so that lint or sludge produced during knitting may be automatically eliminated by falling through the slots and the space between the slots and the cylinder. Preferably, the guide slots for the inner ends of the sinkers are spaced inwardly from the needle cylinder.

Referring now more particularly to Figs.1 and 2, there is shown a needle cylinder body 10 with an upper ledge 11 on which the sinkers 12 ride. As is well known in the knitting machine art, the sinkers are mounted on slotted sinker dial 13, the radially arranged slots 14 in the dial holding the respective sinkers for radial reciprocating movement therein. A conventional annular sinker cap 15 is mounted over the outer ends of the sinkers. All of this structure is conventional, as is the needle mounting which is not shown in these figures to clarify the illustration of the invention.

In contrast to conventional needle cylinders whose ledge 11 was slotted to receive the sinkers, my ledge 11 has a smooth riding surface and the inner ends of the sinkers 12 are held in position by guide slots 16 which are inwardly spaced from the cylinder body 10, leaving a space 17 between the cylinder body and the guide slots. Obviously, when the sinkers 12 are radially reciprocated in their guide slots, any lint, sludge or dirt produced during knitting will drop through the slots and space 17.

The structure of the support for the sinker guide slots may take any suitable form and those shown are merely given by way of example. As illustrated in Figs. 1 and 2, the guide slots are machined into an arcuate metal ring 18 which is welded or otherwise fixed to support ring 19. The slotted ring may be screwed on or otherwise fixed to its support. The slotted support ring is bolted to the needle cylinder at 20, 20. Any suitable mounting may, of course, be used. Also, instead of providing a slotted ring 18, individual arcuate metal blades could be welded to the support ring 19, such blades being spaced so as to receive a corresponding sinker between two adjacent blades. In this arrangement, pairs of adjacently mounted blades would form the guide slots 16. Other slotted structures may be devised by the machinist after he benefits from the essential teaching of the present invention, requiring the spacing of the sinker guide slots from the needle cylinder.

A preferred embodiment of the sinker guide slot mounting according to my invention is illustrated in Fig. 3. The top pontion of the circular knitting machine shown in this figure includes the conventional needle cylinder with its sinker dial 103 and sinker cap 105, sinkers 102 being mounted in radial slots 104 in the sinker dial and held in position by the sinker cap. The needle cylinder is provided with longitudinally arranged grooves 111 holding needles 112 which are axially slidable in grooves 111 :in a manner-knownper se. The identical needle mountingmay be-used innthe needle cylinder of Fig. l where it has beeneliminated to clarify the showing.

The:.d ifierence between the embodiments of Figs. 1 and" 3 lies in-the zspecific configuration of the sinker guide slots. "While the. guide slots are inwardly spaced from the needle cylinder'in both embodiments, the'slot supportring -IQ is relatively close to the needle cylinder in the embodiment of Fig. 1. In the embodiment of Fig. 3, -on the other hand, sinker: ring'199 is far removedfrom the needle cylinderandtheiguide slots'ltldare ofdifierent shape. l'hesinkerring liiT-is arr integral member of L-shaped cross section and isattached to the needle cylinder -by.means of bolts 110. Slots 106 are machined intothe-horizontalflange portions of the sinker ringto provide. the 'guide slots for-the sinkers. v Fig. .4 schematically illustrates yet anotherembodiment of the invention, all conventional structures being identical with :the circular knittingmachine cylinder shown in Fig. 3. In thisembodiment, the needle cylinder 2%. is provided with a -steppedtopconsisting' of shoulder 211 and ledge 261 on which the sinke-rs 262 ride. Sinker ring 209 is bolted-at ililti to' the needle cylinder .below chamber 207, the sinker ring being slotted at 206, similarly to the embodiment of Fig. 3. In the embodiment of Fig. 4, too, lint "tending to collect in the sinker guide slots will simply drop intorecessed chamber 267 and will be removed-mostly through slot portions 206a into theopen interiorof the cylinder where it will fall on the floor or. machine support-base. Dirt accumulating in chamber207 after. operation of considerable duration can be removed bycccasionally taking off ring 2tl9 toclean the machine. Nevertheless, even this embodiment of-the invention constitutes a considerable improvementover conventional needle cylinders, not only 'becauseof its substantialselfrcleaningfeature but also because it pro vides a smooth-top ledge which can be readily tempered or hardened. Also, the packing of-lintbehind the needle will be avoided, at-least for asubstantial period-of time, because most of the dirt will-be removed through slot-,portions 206a and any accumulation chamber-ZilTwill-be very slow.

In addition to the self-cleaningfeature common to all embodiments of the -invention, it will-be noted that-the upper ledge o-fthe needle cylinder; upon which the sinkers ride is always a smooth metal-ring which, therefore, constitutes no problem in hardening. It has been found that the slotted upper rimsof conventional metal needle cylinders are very diflicult to temper'or cannot be satisfactorily hardened at all. Accordingly, the guide surfacesfor the sinkers inthe needlecylinders of the prior art are often relatively soft so that the rapidly reciprocating sinkers tend to bite into the cylinder, forming irregular grooves which cause further irregularities in the sinker movements. In contrast to this, the smooth metal ledgesotthe needlecylinders of the present in vention can be tempered without difficulty, thus providing hard riding surfaces for the reciprocating sinkers.

While I have described the improved needle cylinder of my invention with reference to specific embodiments, it will be obvious that I am not concerned with any specific cylinder shape, needle mounting, sinker, sinker dial or sinker cap, nor with any specific slotted ring for guiding the-inner ends of the sinkers, the only essential requirement being that the guide slots for the inner' ends of the sinkers are spaced, preferably inwardly, from the cylinder body, leaving a space'between the'body and the guide slots. Many'variations and modifications may .occur to the sk' led in the art within the framework of the st'atedrequirement without departing from the spirit and 3. scope of this invention as defined in theappended claims.

What I claim is:

l. A needle cylinder for-a circular knitting machine, comprising a substantially smooth upper ledge, a plurality of sinkers radially arranged and riding on said ledge with an inner portion of the sinkers extending inwardly from the ledge, and annular guide slot means. defining a plurality .of radiallyextending slots ,openingintothe interior ofithe-cylin'der-and guidingi-the inner portions of said sinkers,the guide slots being spaced and extending inwardly; fromzsaid cylinder. ledgeaand guide-slot means and the cylinder. adjacent the.ledge. defining an open space inwardly'of the" ledge.

2. The needlegcylinder-cfclaim 1; wherein said smooth upper ledge is of hardened metalto constitute a wearresistant riding surface for the sinkers.

3. A needle cylinder for a' circular knitting machine, comprising a substantially smooth upper. ledge, a plurality of .sinkers radially .arrangediand riding on said ledge with an'inne r .,-portion of thesinkersextendinginwardly from the ledge; and; :an annular--. sinker; guide -rnember, defining a plurality of radially extending slots opening into the-interior.of-lthegcylinderand guiding the inner portions-of .the sinkers, the sinker guide member being spaced vertically from said ledge and extending inwardlyfrom the cylinder, a major part of'said slots extendinginwardly from said cylinder and said inwardly extending guide slot member andthe cylinder forming an open space therebetween.

4. A. needle cylinder :for. a circular knitting machine, comprising asubstantially smooth upper-ledge, a plurality of sinkersradially arranged and riding on said ledge with an inner portion of the sinkers' extending inwardly from the ledge, a'sinker guide ring spaced verticallyfrom saidledgeiand having a plurality of radially extending slots openinginto the interior of the cylinder and guiding the inner portions of the sinkers,.and meansifor supporting the sinker guide ring 'on' the cylinder in inwardly spaced-concentric relationship thereto, at least a major part of the :guide slots extending inwardly from the cylinder; saidsinker guide ring'and the cylinder forming an open space .therebetween.

5. The needle cylinder of claim 4ywherein said sinker guide .ring'comprises an outwardlyflared upper portion provided-with said radially extending slots and a 'solid support-portion wheretosaid slotted upper portion is connected, said upperportion extending with itsslots from the solid-support portion substantially to the circumference of the cylinder but spaced upwardly from the cylinder-ledge.

- 6. lTheeneedle cylinder of claim 4; wherein said. sinker guide ring is TOf substantially L-shaped .cross section having asolidcylindrical support portion and 'an' upper slotted portion extending horizontally therefrom toward the'cylinder but inwardly spaced therefrom.

7. A needle cylinder for a circular knitting machine, comprising a stepped top consisting of :a smooth upper ledge and a shoulder, a plurality :of 'sinkers arranged and riding on said ledge with an:inner portion of the sinkers extending inwardly. from-theiledge, asinker guide ring spaced vertically '-from the ledge and having a plurality of radially extending slots opening into the interior tofthe cylinderand guidingthe inner portions of the sinkers, and means forrsupporting the sinker guide ring on the cylinder below said shoulder, at least amajor part of the guide slots extending inwardly from said. ledge towardsaid supportingmeans, said inwardly spaced guide slotparts,.said .shoulderand said ledge defining a recessed chamber.

References Gitedin theifile of this. patent UNITED STATES PATENTS 421,147 vScott et.al.. Feb. 11,1890 69,672 Lawson Feb. 2, 1937 2 ,154,384 Richter Aprxll, 1939 

